title: Prophylactic supraclavicular radiotherapy after surgery in high-risk n1 breast cancer.
abstract: OBJECTIVE
  To evaluate the role of prophylactic supraclavicular radiotherapy (RT) by comparing the clinical outcomes of locoregional recurrence (LRR) in high-risk N1 breast cancer.
  
  
  METHODS
  We performed a retrospective comparison study of 250 high-risk N1 breast cancer patients treated at two institutions. Patients were considered to be high-risk when they had more than two of the following risk factors: lymphovascular invasion, extracapsular extension, metastasis to more than two axillary lymph nodes (ALNs), or level II or higher ALN metastasis. We compared two groups treated with different adjuvant RT fields for the purpose of prophylactic supraclavicular RT (SCRT).
  
  
  RESULTS
  Among the 250 patients, 97 patients received SCRT while 153 did not. During follow-up, 32 patients (7 in the SCRT and 25 in the no-SCRT group) had recurrence, and LRR developed in 19 patients, 18 of whom had not received SCRT. In multivariate analysis, SCRT [hazard ratio (HR) 0.072; p = 0.011] and chemotherapy regimen (cyclophosphamide, Adriamycin, and taxane; TAC) were the significant prognostic factors in LRR-free survival (HR 0.385; p = 0.046), and chemotherapy regimen also showed significance for distant metastasis-free survival (HR 0.399; p = 0.037).
  
  
  CONCLUSIONS
  Use of prophylactic SCRT may reduce the risk of LRR in patients with high-risk N1 breast cancer.
authors.affiliation: Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jeong Il
authors.initials: JI
authors.lastname: Yu
authors.forename: Won
authors.initials: W
authors.lastname: Park
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Shin
authors.forename: Nam Kwon
authors.initials: NK
authors.lastname: Lee
authors.forename: Doo Ho
authors.initials: DH
authors.lastname: Choi
authors.forename: Seung Jae
authors.initials: SJ
authors.lastname: Huh
mesh_terms: D000328:Adult; D000368:Aged; D001365:Axilla / Q000473:pathology; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D017024:Chemotherapy, Adjuvant / Q000379:methods; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000379:methods; D012189:Retrospective Studies